1. Field of the Invention
This invention relates to the shaping of glass sheets to be laminated, and, in particular, relates to the simultaneous shaping of a pair of glass sheets having a non-rectangular outline of non-uniform curvature in plan by a combination of gravity sag bending and press bending to a complicated shape including a longitudinal bend about a transverse axis of curvature and a complicated bend containing both convex and concave elements in elevation about a longitudinal axis. The bending to such complicated shapes requires that the glass sheets be supported in precise alignment with each of the molds used to impart the different components of the complicated bend to which the glass sheets are to be shaped. Such complicated shapes are required to enable the shaped glass sheets to be mounted in a curved mounting frame forming part of an automobile body so that the curved glass forms a laminated window that merges with the shape of the curved mounting frame and the vehicle body in which it is mounted.
2. Description of Patents of Interest
U.S. Pat. No. 2,570,309 to Black sag bends a single glass sheet to conform to the contour of a circular metal outline mold, then lifts the sag bent glass sheet on a concave pressing mold toward an upper convex pressing mold of complementary shape to complete the bending. The press bent glass sheet is lowered to the circular outline mold for transfer to a cooling station. No cycle of rapid and slow rates of movement is provided for the lower pressing mold. The apparatus of the Black patent is practical only for fabricating glass sheets of circular outline to shapes where misalignment does not result in failure to be able to match the shape of the glass sheet with that of the frame in which the bent glass is to be installed.